Acronym. Stands for Shoot And Buy ANother One. Shorthand veterinary term for ill/ diseased pet animal that owners are, more politely, advised to have put down/put to sleep/ euthanised. Can also be used outside vet medicine to describe a useless or irritating person

"Was that Mrs Smith with Tiddles the cat? Yeah, 14 years old, diabetic and incontinent. Complete sabano in my opinion."